Giving mobile radio devices a unique equipment or serial number, also known as the IMEI (International Mobile Equipment Identity) is known under the standards for mobile radio networks currently in use. The IMEI is the fifteen-character code which is used by GSM (Global System for Mobile Communication) networks in current use to identify a mobile radio device belonging to a mobile radio network. The IMEI can usually be shown on the display of the mobile radio device by entering a specified code on the keypad of the mobile radio device. The IMEI is also printed inside most mobile radio devices, preferably in the battery space, if battery-powered mobile terminal equipment is involved.